Novel coal feeder for production of low sulfur fuel. Annual technical progress report, September 1, 1989-October 1, 1990 | Health & Environmental Research Online (HERO)

HERO ID

1781793

Reference Type

Technical Report

Title

Novel coal feeder for production of low sulfur fuel. Annual technical progress report, September 1, 1989-October 1, 1990

Author(s)

Khang, SJ; Keener, TC

Year

1990

Report Number

NTIS/02973994_a

Volume

GRA and I

Issue

GRA and I

Abstract

The project objective is to study the feasibility of an advanced coal desulfurization concept in a coal feeder. It is proposed to construct a novel coal feeder which contains dual screw tubes, the inner tube acting as a coal pyrolizer and the outer tube acting as a desulfurizer with hot calcined limestone pellets or other renewable sorbent pellets. The inner screw feeder pyrolyses coal particles in a reducing environment which produces sulfur-containing gases such as H(sub 2)S and COS. Hot calcined limestone pellets (or other renewable sorbent pellets) are added to the outer tube and react with sulfur components. Based on the published data on both the pyrolysis and the limestone-based desulfurization, the proposed system is expected remove between 50 and 80% sulfur from various high-sulfur coals. Advantages of this scheme are: (1) maximum utilization of limestone up to a 100% conversion, (2) treatment of low volume sulfur-containing gas before mixing with high volumes of air and combusted gas, (3) efficient usage of thermal energy, (4) easy renewal of heat transfer surface since the wall surfaces are mechanically cleaned by the screw feeders, (5) easy applicability for retrofit to various processes such as conventional coal combusters and coal gasifiers, and (6) a possibility of calcium oxide regeneration from CaS. (Or easy recycle of other used sorbents). Works under progress are (1) literature review on coal pyrolysis, (2) computer/math modeling of the pyrolysis section, (3) evaluation of pyrolysis kinetics, and (4) experimental pyrolysis in an auger feed tube. 9 refs., 15 figs., 4 tabs.

Keywords

Bituminous Coal; *Fuel Feeding Systems; *Desulfurization; Adsorbents; Ash Content; Calcium Oxides; Calcium Sulfides; Carbon Oxysulfide; Chemical Reaction Kinetics; Cleaning; Coal Gasification; Combustors; Design; Devolatilization; Efficiency; Gas Generators; Gases; Hydrogen Sulfides; Limestone; Maintenance; Mathematical Models; Moisture; Particle Size; Progress Report; Pyrolysis; Regeneration; Retrofitting; Sulfidation; Sulfur Content; Temperature Dependence; Time Dependence; Volume; Coal preparation; *Air pollution abatement; EDB/010402; EDB/010409